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[11:00:00] CAROL COSTELLO, CNN ANCHOR: More than 1,000 Long Islanders lining up to pool their money, $10 each. Any winnings will be split evenly. So far they've collected $10,000 to buy tickets. Good luck.

(LAUGHTER)

Thank you so much for joining me today. I'm Carol Costello.

AT THIS HOUR with Berman and Bolduan starts now.

ANNOUNCER: This is CNN breaking news.

JOHN BERMAN, CNN ANCHOR: Hello, everyone. I'm John Berman.

KATE BOLDUAN, CNN ANCHOR: I'm Kate Bolduan.

We begin with breaking news right now. We've got a race, folks. Brand-new poll numbers just out from Monmouth University show that Bernie Sanders with his biggest lead yet over Hillary Clinton. This is in New Hampshire. A 14-point lead. Take a look. Sanders is now at 53 percent, Clinton 39 percent. Back in November, the same poll had Clinton leading by three points.

BERMAN: He leads just about every group you can imagine, registered Democrats, 50 to 42. Two months ago, Clinton was in front. Independents, it's 58 to 34. Seniors, it's 50 to 44. Take a look at this. Women, Bernie Sanders leads Hillary Clinton with women, 50 percent to 44 percent.

So how will Hillary Clinton respond today? We're about to find out? She's set to speak to Iowa State University. You're looking at live pictures right now. This event scheduled to begin any minute.

CNN senior political correspondent, Brianna Keilar, is there.

Brianna, you know, trailing in New Hampshire now by a lot, Hillary Clinton is, barely out in front in Iowa. This campaign is getting very tough for Hillary Clinton.

BRIANNA KEILAR, CNN SENIOR POLITICAL CORRESPONDENT: It certainly is. And I think you can see by just how much she's stepping up the attacks on Bernie Sanders in recent days. Something she really hasn't done for her entire campaign. You can see how much concern there is in her campaign. At the same time, John, talking to sources in the campaign, they feel they have a pretty good ground game in Iowa, they are organized, they have volunteers, they have more engaged supporters. They're looking at the polls when it comes to likely caucus-goers and they think they can count on a bigger lead there, that their supporters are more likely to show up on the day of the caucus and make the case for Hillary Clinton to be the winner here in Iowa. Certainly, it's too close for comfort.

You notice talking to Bernie Sanders, I talked to him yesterday, he's almost gleeful with how the race is tightening in Iowa. For Hillary Clinton's campaign, part of the strategy for dealing with Bernie Sanders having the lead in New Hampshire has been to try to pull out the win in Iowa, try to create momentum, make her seem like the candidate who can win the nomination so going into New Hampshire she can build on that and maybe change the mind of some voters who are uncommitted.

She's putting an emphasis here in Iowa. It's pretty interesting, on electability, making the case she has a better shot in a general election than Bernie Sanders. The campaign points to poll numbers. Voters asked, who's more electable? They feel Hillary Clinton is. What's really getting in the way of this argument of Hillary Clinton here in Iowa is that in these hypothetical match-ups, at least in polls in Iowa and New Hampshire, between the Democratic candidates and Donald Trump and Ted Cruz, Bernie Sanders is actually performing better and so because of that he's really undercutting her argument, or certainly trying to, as he makes his case here to potential caucus- goers in Iowa -- John and Kate?

BERMAN: Brianna Keilar in Iowa.

We'll keep our eye on that stage. When Hillary Clinton takes the stage, we want to see how she'll respond to this new shape of a race.

Joining us, CNN chief political analyst, Gloria Borger; CNN political commentator and former Obama adviser, Dan Pfeiffer; and Doug Heye, former communications director at the RNC.

Dan, eight years ago, you were working in a heated Iowa and New Hampshire race. Hillary Clinton just a month ago in New Hampshire was leading Bernie Sanders in the Monmouth poll. Now she risks falling behind in Iowa as well. What's going on here?

DAN PFEIFFER, CNN POLITICAL COMMENTATOR: This was always going to be a close race in the first two states. The best thing Hillary can do to do well in New Hampshire is win Iowa. I think their focus is in the right spot. Historically the results in Iowa affect the New Hampshire polls. The challenge for Sanders comes after New Hampshire. Can he demonstrate any ability to expand coalition and compete in states like South Carolina, Nevada and the rest of the country? Until he can do that, he's very limited to those two first -- those two first states.

BOLDUAN: Doug, let's say, so they're neck and neck right now in Iowa. He's ahead. He has these big new numbers come out in New Hampshire. Let's say Bernie Sanders ekes out a win in Iowa and then wins in New Hampshire. If he has that momentum coming out of New Hampshire, those two first big wins, can Hillary Clinton pull it out after that?

DOUG HEYE, CNN CONTRIBUTOR & FORMER COMMUNICATIONS DIRECTOR, RNC: I think she can. She should be strong in South Carolina, should be strong in the southern states. That's why I was curious to see if the Clinton campaign rolled out endorsement of former Charlotte mayor, Anthony Fox in Iowa, as opposed to doing it in South Carolina to get the South Carolina media market, as you know working in North Carolina, that covers a whole lot of South Carolina. Hillary has a strong campaign but there's uneasiness, not just with independent and Republican voters but with Democratic voters. She's struggled to form a strong message. We'll have to see if she steps up her attacks on Bernie Sanders but if she does so on the air waves and digital.

[11:05:37] BERMAN: It's interesting. It will be uncomfortable, right? Maybe Hillary Clinton can do it but it will be uncomfortable. The only candidate to do it?

BOLDUAN: I don't know. You taught me this trivia.

BERMAN: Bill Clinton. Lost Iowa and New Hampshire and went on to win the nomination.

Gloria, how do you think we got here over the last few weeks? It feels like something changed for Hillary Clinton because she did seem to have solid leads in Iowa. She seemed to be performing better in New Hampshire. What changed over the last two weeks to change this?

GLORIA BORGER, CNN CHIEF POLITICAL ANALYST: I think people started focusing a little more on their candidates, as happens after Christmas. Hillary Clinton has been behind in New Hampshire by varying degrees and we have -- one poll recently showed them neck and neck. Now she's really behind. New Hampshire has always been a bit problematic for her. The focus on Iowa, as Dan was saying, is really important. And I think that people like Bernie Sanders. I spoke with the vice president yesterday about this. And his point was that Bernie Sanders has a lot of credibility on the income inequality issue because he's been talking about it his entire career. So if you're worried about, that you look at Bernie Sanders. If you're a liberal Democrat and you say, well, you know, he's talking my language.

BOLDUAN: Gloria, that was one of the many fascinating parts of your interview with Joe Biden. We can't -- he want to emphasize that moment because what the vice president said, how he effusively praised Bernie Sanders and then as you pressed him about Hillary Clinton, it was remarkable. Listen to this.

(BEGIN VIDEO CLIP)

JOE BIDEN, VICE PRESIDENTIAL CANDIDATE: Bernie is speaking to a yearning that is deep and real. And he has credibility on it. And that is the absolute enormous concentration of wealth in a small group of people with the little class now being able to be shown being left out. There used to be a basic bargain. If you contributed to the profitability of enterprise, you got to share in the profit. That's been broken. Productivity is up. Wages are stagnant.

BORGER: Hillary is talking about that as well.

BIDEN: Well, but it's relatively new for Hillary to talk about that. Hillary's focus has been other things up to now. That's been Bernie's -- no one questions Bernie's authenticity on those issues.

(END VIDEO CLIP)

BOLDUAN: Gloria, you -- you know Joe Biden very well. You've covered him for a very long time. He's also -- he's been in this game a very long time. What is he doing? What is he saying there?

(LAUGHTER)

BORGER: Well, I think a lot of people were asking that question. And this morning he tried to walk it back. He was asked about our interview on NBC and he tried to walk it back and said, I was saying she's been spending a lot of time on foreign policy. That's his story now and he's sticking to it. I think that what he was saying is that Bernie Sanders has an awful lot of appeal on this issue because he has made it his life's work. And I think Sanders' populism appeals to Joe Biden. Maybe Dan can talk about this a little bit. Really appeals to Joe Biden. It's no secret Joe Biden was thinking about running against Hillary Clinton, so there's still that in the back of his mind. However, would he go out and effusively campaign for Hillary Clinton if she were the Democratic nominee? Absolutely. I don't think there's any question about that.

BERMAN: If she becomes the Democratic nominee, but there's a long way to go before that and a long time for Joe Biden to say other things and he did sort of try to take it back today, Dan. But there are no backsies in politics.

(CROSSTALK)

(LAUGHTER)

PFEIFFER: There are tons of backsies.

(LAUGHTER)

BERMAN: Joe Biden said what he said, Dan. This is going to irk Brooklyn. I have to imagine the Clinton campaign is, we don't need this. We have enough problems with Bernie Sanders. We don't need Joe Biden saying stuff like this.

[11:09:46] PFEIFFER: I don't know how my friends in Brooklyn reacted to it. I think Gloria is right on two points. One the vice president was making, a very accurate point of political analysis, which is, if you were a voter who -- in the Democratic party who cares a lot about income inequality, Bernie Sanders has been your champion for a very long time. Hillary Clinton has been secretary of state for four of the last six years and not been talking about it nor should she be. She's worked on those issues for a very long time, going back to the beginning of her career. Gloria is also right that the vice president, I think, identifies with -- maybe not all the solutions that Bernie Sanders has, but with this idea because it's been core to the vice president's identity as someone who has always made his political career as fighting for the working class families he work up in my home state of Delaware. So, I think that does appeal to him. Had he run, he would have run a very populous campaign championing working folks in the middle class. So, I think he was -- I don't think he was trying to, as he said this morning, make a negative point about Hillary Clinton. Obviously, the press jumped on that. And that's the danger of a politician playing the role of political analyst.

BOLDUAN: That's what happened when Joe Biden talks sometimes. Sometimes he says what he means -- he says what he means maybe and not exactly what he's supposed to say.

(LAUGHTER)

I'm kidding.

Doug, final question to you because I know you love giving advice to the Democratic candidates. What would you say to Hillary Clinton right now? She's going to be taking the stage -- she's taking the stage in Ames, Iowa. How does she address this?

HEYE: I think she started stalking about guns. That's an issue that plays pretty well to the Democratic base. I think you'll see her emphasize that more. At the same time, she's got to make sure she has all cylinders firing in the right direction. We know Joe Biden is not going to go into that good night. This is grade "A" trolling from Joe Biden. She needs to get him on the phone and make sure he's talking on message, whether he's going to be a surrogate for her campaign or not.

BOLDUAN: No one put Joe Biden on message. Some kind of rendition of don't put baby in the corner, I think.

(LAUGHTER)

(CROSSTALK)

BERMAN: Successful all ready.

Thanks, guys. Great to see you.

According to the Republican front-runner, Donald Trump's dream date for the general election, you ask, who is that? Oh, Bernie Sanders. Not necessarily Hillary Clinton that you're looking at right there. In light of the new poll numbers, could his dream come true? We'll speak live with Ben Carson's former campaign manager, who told us Donald Trump could be the inevitable nominee.

BERMAN: Plus, a terror attack on one of the great tourist hubs. The prime suspect, ISIS. We're going to take you there live.

And new this morning, Sean Penn giving his very first reaction to the backlash about his secret meeting with el Chapo. And new pictures that show he was watched during his trip.

(COMMERCIAL BREAK)

[11:16:28] BERMAN: Let's talk Republicans, shall we, because there has been a shakeup on the Republican debate stage. Some shrinkage, if you will. Only seven candidates will make it. That means two who have been there will not, Carly Fiorina and Rand Paul, ladies and gentlemen. Rand Paul relegated to the undercard, but, but --

BOLDUAN: But, he says he's not going to show up. He says he is a first-tier candidate. He's not going to be in a second-tier debate.

Here to weigh in on this and much more is former Ben Carson campaign manager, Barry Bennett.

Barry, it's great to see you.

BARRY BENNETT, FORMER BEN CARSON CAMPAIGN MANAGER: Great to see you. Thanks for having me.

BOLDUAN: Rand Paul relegated to the undercard. Says he's going to skip it. What do you think?

BENNETT: Well, I mean, I think it might be stubborn pride. There's going to be a lot of people will be watching the undercard. I think you're giving up those viewers. Not the wisest thing to do. I understand it's tough, it's frustrating, but it's out of your control, so you should talk to the viewers that will watch you.

BERMAN: Suck it up and go?

BENNETT: Yeah.

BOLDUAN: Can he change now? What if he says, I'm going to show up now, even though he says, I'm not going to?

BENNETT: It's a politician. Of course, they can flip-flop.

(LAUGHTER)

BERMAN: On that line, Donald Trump, when you spoke to us last week, you said, unless something cataclysmic happens, Donald Trump will be our nominee.

BENNETT: Right.

BERMAN: Has anything cataclysmic happened? Do you still believe that to be the case?

BENNETT: No. The latest polls show him gaining strength in Iowa and New Hampshire. I don't see anything yet. There are going to be a lot of people at the debate taking their last swing. If they don't connect, this is rapidly becoming over. The fat lady hasn't sung but she's warming up

BOLDUAN: That's very interesting, especially when we talk in relation to your former campaign, Ben Carson. There was some more not great news for Ben Carson coming out of New Hampshire. Super PAC employees leaving the super PAC in New Hampshire, joining as volunteers with the Ted Cruz campaign -- or joining as volunteers for Cruz. He's slipping further, Ben Carson, further in the polls. Who Benefits from that now?

BENNETT: Probably Ted Cruz and Donald Trump both. If you look, second-choice voters for Ben are evenly divided between those two. I don't think it makes a huge impact. They probably divide up between the two evenly. Unlike the other side, it is establishment lane where they're fighting each other very nasty but just because I attack candidate "X" doesn't mean I get his votes. They're going to go to "Y" and "Z." In the non-establishment lane, it's a three-way race. So I don't think anybody's going to make any major movement.

BERMAN: Who do you think the next to go is? Who do you think the next to drop off is? Who do you think the next two or three is? What's the order right now?

BENNETT: Obviously, Carly and Paul are probably, you know, the ones that are in critical condition. After Iowa and New Hampshire, you'll probably see two, three more people get out. By the time we get to South Carolina, it could be a much narrower race?

BOLDUAN: Is Ben Carson one?

BENNETT: I wouldn't be surprised. I don't have any inside information, but I wouldn't be surprised.

BOLDUAN: On Ben Carson, he spoke to -- Dr. Carson spoke to CNN this morning. Some of the biggest mistakes that happen in the campaign was every interview with "New Day."

BENNETT: "New Day."

(LAUGHTER)

BOLDUAN: So he spoke to "New Day" this morning, and here's what he said about debate prep.

(BEGIN VIDEO CLIP)

[11:20:00] DR. BEN CARSON, (R), REPUBLICAN CANDIDATE & RETIRED NEUROSURGEON (voice-over): You'll see a lot more energy behind the responses because, again, I don't have that weight on my shoulders now. I have a very vibrant organization that truly provides the kind of information and the help that is needed.

(END VIDEO CLIP)

BOLDUAN: Let me paraphrase that for you, Barry. He said that he's got a lot more energy. He's going to have a lot more energy behind his responses. Because he doesn't have that weight on my shoulders now he said that this morning and it stuck out to a lot of us as ouch. Basically he said he was being held back before. I want you to respond. BENNETT: You know, when they announced this shakeup on the 23rd,

which got this whole thing going, they said it was because I was being too aggressive and that he didn't want to be that guy. And this morning it's --

(CROSSTALK)

BOLDUAN: This seems the opposite of that.

BENNETT: Yeah.

BOLDUAN: What do you make of that?

BENNETT: I love Ben and I'm going to be rooting for him this week. But I don't know that it's a coherent message.

BERMAN: You don't know that it's a coherent message that he's sending. Which some people suggested is the message that you received on the debate stage at some point. Which has led many to wonder, what is debate prep like for Ben Carson? I'm wondering if you can give us a window into that.

BENNETT: A lot of experts in the room talking about issues. He's asking them questions. He's a very, very smart man. The narrative that Ben Carson doesn't understand foreign policy or that kind of stuff is completely wrong. We wanted him to be more aggressive than he was comfortable being. You can't blame him for staying inside his skin. We'll see what he is this week. My guess is he's not going to be a John Kasich or a Donald Trump. He's going to be --

BOLDUAN: That's what I was going to ask you. What does an aggressive Ben Carson look like? I'm not trying to be cute here. We haven't seen it. I mean, that's not who he is, as you've told us.

BENNETT: Some candidates fall into this trap that winning the debate means you give the best answer and they don't quite get that's really political theater, not a real debate. I don't know that Ben is going to be an expert at political theater. He can be an expert on any policy you throw in front of him. He's very, very smart.

BERMAN: You said a bunch of people on the stage, last two debates heading into Iowa and New Hampshire, a lot of these candidates will throw their last best swing at Donald Trump.

BENNETT: Yeah. They better.

BERMAN: How do you land one?

BENNETT: I don't know. Nobody has been able to for the last 11 months.

BERMAN: How would you?

BENNETT: I don't know. I think you have to get to something Donald Trump thinks is an asset that you can turn into a liability and no one's been able to do it. BOLDUAN: That's the genius of Donald Trump.

BENNETT: Yeah.

BOLDUAN: Every misstep he's made, he has turned into a plus for him.

BENNETT: Well, I think that it's kind of a -- we need to look at politics afresh, anew, that all these things we think are missteps really aren't. You know, that's just --

(CROSSTALK)

BENNETT: We train ourselves to believe --

(CROSSTALK)

BOLDUAN: How much has Donald Trump surprised you? You were inside a campaign, looking at strategy and how to boost your candidate and beat Donald Trump.

BENNETT: He's better than everybody told me he was. He's a faster learner. He's very smart. He's very smart guy. I mean, he's got the Sunday shows eating out of the palm of his hands. He phones in from home and they take a feed because he's delivering ratings and delivering talking points. It's wonderful.

BOLDUAN: You say wonderful, you say he's inevitable. Do you say that with sadness, though? What do you think of Donald Trump?

BENNETT: I mean, I admire him. You know, he's been very, very successful. And he's a lot better at politics than anyone thought he was. And he understands what the people are thinking.

BOLDUAN: Is he good for the Republican Party?

BENNETT: Well, you know, it seems to be. They're turning out 12,000 a night at rallies. You know, he's -- I think when they start raising money for people, they're going to raise a ton of money. I think he excites -- we used to call them Reagan Democrats. I would call them Trump voters. He's exciting a lot of people out there.

BERMAN: Last question, quick prediction in Iowa. Who's first, second, by how much?

BENNETT: I think it's right now Trump and Cruz, neck and neck. I would say it's a push.

BOLDUAN: All the way to the end.

BERMAN: Barry Bennett, great to have you with us.

BENNETT: Thank you.

BOLDUAN: Great to see you, Barry.

BENNETT: Thank you.

BOLDUAN: Thank you so much.

BERMAN: It's being called a devastated crisis. Families in one American city still without clean water after officials tried cutting costs. Right now response teams are going door to door.

[11:24:33]BOLDUAN: Also just in, some breaking news. Your odds to win the biggest jackpot in history --

(LAUGHTER)

-- just got even a little more depressing. Because none of you are going to buy tickets anymore because I'm buying them all. Here's what the Powerball grand prize is now. We'll tell you after the break.

(COMMERCIAL BREAK)

BERMAN: A deadly terror attack this morning at one of the great tourist hubs. A suicide bomber killed at least 10 people in a popular and heavily guarded square in Istanbul. Turkish officials say the attacker was with ISIS and came into the country from Syria.

BOLDUAN: Many of the victims, they were German tourists. Germany is urging its citizens to avoid tourist attractions and large gatherings in Turkey.

CNN's Arwa Damon is there. She's at the site of the blast.

Arwa, what more are you learning?

ARWA DAMON, CNN SENIOR INTERNATIONAL CORRESPONDENT: We're just outside the police cordon here. The attack happened around 10:15, 10:20 this the morning. That Bent off in the heart, the center of Turkey's historic -- Istanbul's historic tourist districts, one of the main places you would visit if you were coming here as a tourist.

According to authorities, this individual was of Syrian other begin origin, was a member of ISIS. Not someone Turkish officials were tracking. Someone we're being told recently crossed from Syria into Turkey.